Zardari, a frequent visitor to China during his presidency, called on chairman of the China People's Political Consultative Conference (CPPCC) Yu Zhengsheng, the fourth ranking member of the Chinese Communist Party.

He was accompanied by Bilawal and other members of the Pakistani delegation.

Zardari is the second Pakistani politician currently in China. Punjab Chief Minister and Prime Minister Nawaz Sharif's brother Shahbaz is also visiting China, with reports suggesting that he may seek Beijing's support for the embattled Pakistan government.

China and Pakistan both consider each other "all weather" allies.

Zardari's visit to China came as protesters, led by cricketer-turned-politician Imran Khan and populist cleric Tahirul Qadri, camp in the heart of Islamabad for the last two weeks demanding Prime Minister Nawaz Sharif's resignation.

The protesters allege rigging of polls during the general election last year and killing of 14 of Qadri's supporters in Lahore on June 17.

China earlier called on the protesters and the Pakistan government to show restraint and resolve the disputes peacefully.

"China has paid high attention to the current situation in Pakistan," Foreign Ministry spokesman Qin Gang had said about the protests.

"As a good neighbour, China sincerely hopes that all parties concerned in Pakistan will proceed from the fundamental interests of the country and the people and to resolve the crisis in a peaceful way so as to jointly safeguard the stability of the country," Qin said.